1. Field of the Invention
This invention relates to an automobile window glass assembly, particularly an assembly that prevents an automobile window glass from looseness or play in the lateral direction of the vehicle.
2. Description of the Prior Art
As shown in FIG. 1, a mechanism for raising and lowering an automobile window glass 1 includes a lift arm bracket 2 secured to a lower edge portion of the glass 1, a lift arm 3 and a synchronizing arm 4 crossing each other and having one end slidably mounted in a guide groove of the bracket 2, a sector gear 5 secured to the other end of the lift arm 3, and an arm bracket 6 on the side of a door, the other end of the synchronizing arm 4 being slidably mounted in a guide groove of the arm bracket 6. The sector gear 5 is in meshing engagement with a gear 7 secured to a rotary shaft that is operated manually or powered by a motor. Rotating the gear 7 causes the lift arm 3 to pivot about a fulcrum 8 to raise and lower the window glass 1.
Guide rails 9 are secured to the side of the door at both opposing edges of the glass 1. Guide rollers 10 are secured to both ends of the window glass 1 and are slidably fitted into each of the guide rails 9. When the window glass 1 is raised and lowered by the lift arm 3, the glass 1 is guided by the guide rollers 10 so that movement of the glass 1 follows a prescribed path.
An example of the guide roller 10 employed in the prior art is shown in FIG. 2. The details of this arrangement are disclosed in the specification of Japanese Patent Application Laid-Open (Kokai) No. 58-164421. The guide roller 10 includes a cylindrical roller 12 formed of synthetic resin and secured to the head of a shaft 11 secured to the window glass 1, and a cap 13 disposed in an opening of the roller and secured to the head of the shaft 11.
The guide roller 10 has a dimension h within the groove of the guide rail 9, and the groove itself has a dimension H. In the prior-art arrangement shown in FIG. 2, it is designed so that the difference H-h between these two dimensions takes on a positive value, i.e., so that some clearance is left between the wall of the cap 13 and the wall of the groove in the guide rail 9. In other words, if the value of the difference H-h were to be negative, the cap 13 would offer large sliding resistance, thus requiring a large force to raise and lower the window glass 1. To avoid this, therefore, the dimensions are selected so that the difference H-h will be positive. However, owing to the clearance between the cap 13 and the wall of the groove, the window glass 1 vibrates laterally of the vehicle, or up and down in the view of FIG. 2. This constitutes a disadvantage encountered in the prior art arrangement.